This invention relates to an ergonomic controller and, in particular, to a control device for conveying positional and other information from a human operator to a machine.
In the prior art, a variety of mechanisms have been proposed, or even used, to enable a human operator to convey positional or other information to a machine. In the particular case of a computer displaying information on a screen, these mechanisms have taken the form of what are popularly known as joystick, trackball, or mouse, to name a few.
The trackball and mouse have at least one advantage over other mechanisms in that the range of motion is not limited by mechanism itself; i.e. the turning of the trapped sphere in these mechanisms can continue indefinitely in any direction. Between these two mechanisms, there are advantages and disadvantages for each. In the past, one had to choose which type of mechanism to use, e.g. as the cursor control on a computer. The problem of having one or the other mechanisms, but not both, has not been lost on those in the art. U.S. Pat. No. 4,562,347 describes a device which ostensibly can function as either a trackball or a mouse. However, the device described requires a special cradle or other support to function as a trackball. Thus, the problem remains of providing an easily used device which can function as either a trackball or a mouse.
In view of the foregoing, it is therefore an object of the present invention to provide a combination mouse/trackball.
Another object of the present invention is to provide a self-contained mouse/trackball which automatically reverses the sense of motion depending upon its mode of operation.
A further object of the present invention is to provide a combination mouse/trackball having selection actuators enabled in accordance with the mode of operation.